Improvement in electro-magnetic envelopes for safes, vaults



E. HOLMES & H. G. 1100MB. ENVELOPE 0R LINING VFOR SAFES, VAULTS, &c.

Patentedne. 2o, 1870.

anca eine @anni (time EDWIN HOLMES, 0E NEW YORK, N. Y.,AND HEERE o. EooME, 0E JERSEY CITY, NEWST JERSEY.

Letters Patent, No. 110,362, dated December 20, 1870.

IMPROVEMENT IN ELECTRO-MAGNETIC ENVELQPES FOR SFES, VAULTS, &c.

The Schedule referred to in these Letters v.I-atentand making parl: of the same.

To all whom e't may concern same; auml" Figure 2, a transverse section thereof', Vin part.

Similar letters of reference indicate corresponding parts. v

Our invention relates to electromagnetic attachments t'o safes, vaults, and other. structure'esI or inclosures for operating a burglar-alarm, upon any attempt being made to break into or improperlyinterferewith the"sa fevault, or structure; and

The inventionconsists in an electric 'envelope or lining applied to such structure or structures, so that any perforation by ametallic instrument or conductor of said envelope or lining, when thesame is properly connected with a battery and bell, or any severing of its connection with the battery, shall soundan alarm.

The invention comprises a combination of an electric envelope or lining for safes, vaults, and other structures, with a galvanometer or instrument, the' movements of which are produced by variations in a current of electricity from a battery or other electrical apparatus, in connection'with the safe, vault, or strucl ture.

Said invention also includes a peculiar construction of the envelope or lining, by making it of separate parts or plates, which connect with the opposite poles of thebattery, and which are imperfectly insulated from eachother, or are connected with each other. by a reqigtance-coil or medium.

The invention also embraces an envelope or lining of the character specified, made of thin, pliable sheets of metal, and insulated from each other by a, pliable non-conductor, so that when glued or cemented together they form a single sheet. The insulating substance we prefer to useis composed of a coating of Vgum-shellacand paper or cloth.

VReferring to the accompanying drawing-` 'candb represent two thin and pliable plates rof shew metal, so insulated from each other that they will allow of a slight current of ,electricity to pass :from one to the other when the platesrare connected with the opposite poles of a battery.

This insulationis eiiccted either' vby introducing a partial conductor between the plates, or by making the insulating substance so thin in one or more places,

that it will .allow of the passage of a slight current through it,.or a like effect may be produced by perfectly insulating the .plates a and b, as by an insulator, c, and connecting them together by a resisting coil or medium, j, which last, for the purpose ot' more clearly explaining the action of the envelope or lining, is the arrangement shown in the drawing.

The two plates a and b being insulated, as described,

upon the surface of .one of them is glued or cemented another plate or sheet of insulating material, c', and upon this insulator is glued or cemented a thin continuous ribbon, d, of metal, arranged to lie in convo- I utions or in a zigzag manner over the entire surface of said insulator c.

The insulators c c' we prefer to make of cloth or paper, properly coated with guin-shellac, and so that they, like the metallic conductors which they insulate,

are pliable, whereby the whole maybe applied in the form of 'a single sheet as an envelope or lining to a safe, vault, or other structure, or to the inside of a wooden covering surrounding the same.

One end of the ribbon (l is connected, as vby a wire, l, with the one pole of'a battery,'and the other end thereof with the plate a. The resistance-coil f is connected with the plates a and l1 at points g and It, and the plate b connected as by a wire, lc, with the opposite pole of the battery to that with which the ribbon d is connected.

,When the wires le and l are connected as described, a slight current of electricity passing to the ribbon (l, flows around the .entire -safe or vault to the plate af,

through the4 resistance-coil f to the plate b, and'from thence through the wirekto the battery.

Any attenipttc perforate the envelope or lining by a metallic instrument, would establish a perfect electrical connection between the plates a and 11, and the current not beingobliged to pass through thc resistance-coil f, the flow would be greatly increased.

Should an entrance befattem'pte'd by using a nonconducting instrument, they metal ribbon d would be, severed and the circuit broken, or the cutting of either wire k or l would have the same eiiect.

To obtain an alarm from the fluctuation or stoppage of the current, asthus produced, it only requires to connect the wires k and l with a galvauometer, or instrument vthe measurements .of which are produced by variations in a` current of electricity from a battery orwother' electrical apparatus, in connection with the safe, vault, or structure. A bell in connection with Athe..apparatus, may be used to give the alarm.

Whatis here claimed, and desiredto be secured by Letters Patent, is-

1. An envelope or lining for safes, vaults, and other structures, composed of two parts or conductors imperfectly insulate# from each other or connected with each other through .a resistance-coil or medium, and in connection with the opposite poles of a battery or other electrical apparatus, for action as specified.

2. The combination of an electric envelope or lining for safes, vaults, and other structures, with a galvanoineter4 or instrument, the movements of which are produced by variation in a current of electricity from' a battery or other electrical apparatus, in connection with asafe, vault, or structure, substantially as herein described.

Witnesses:

HENRY C.'BANKS, ANDREW BUSCH, Jr. 

